rozwiaz
a) 3x(x-1)+5=0
b) 10x2+9=-15x(x-2)​


Odpowiedź :

[tex]a)\\3x(x-1)+5=0\\3x^2-3x+5=0\\\Delta=(-3)^2-4*3*5\\\Delta=36-60=-24\\\Delta < 0 \text{ - brak rozwiazan}[/tex]

[tex]b)\\10x^2+9=-15x(x-2)\\10x^2+9=-15x^2+30x\\10x^2+9+15x^2-30x=0\\25x^2-30x+9=0\\\Delta=(-30)^2-4*25*9\\\Delta=900-900=0\\x_0=\frac{-(-30)}{2*25}=\frac{30}{50}=\frac35[/tex]

a)

[tex]3x(x-1) + 5 = 0\\\\3x^{2}-3x+5 = 0\\\\a = 3, \ b = -3, \ c = 5\\\\\Delta = b^{2}-4ac = (-3)^{2} -4\cdot3\cdot5 = 9 - 60 = -51[/tex]

Δ < 0, brak rozwiązania

b)

[tex]10x^{2}+9 = -15x(x-2)\\\\10x^{2}+9 = -15x^{2}+30x\\\\10x^{2}+15x^{2}-30x + 9 = 0\\\\25x^{2}-30x + 9 = 0\\\\(5x-3)^{2} = 0\\\\5x-3 = 0\\\\5x = 3 \ \ /:5\\\\\boxed{x_{o} = \frac{3}{5}}[/tex]